Technical Field
The present invention discloses a method and apparatus for fabricating a conjugate fiber and a conjugate fiber fabricated thereby. More specifically, the present invention relates to a method and apparatus for fabricating a conjugate fiber, of which resins having different properties are continuously and alternatively mixed in a longitudinal direction of the fiber, and a conjugate fiber fabricated thereby.
Background Art
In general, an apparatus for fabricating a conjugate fiber widely known in the art includes, as illustrated in FIG. 1, a plurality of hoppers 1 that supply at least two granular resin materials, a melting extruder 2 that melts and extrudes the granular resin materials supplied from the respective hoppers 1, a metering pump 7 that measures the molten resin supplied from the respective melting extruders 2 by a specific amount per unit time and feeds it to a spinning nozzle unit 3, the spinning nozzle unit 3 that feeds the molten resin supplied from the respective metering pumps 7 via a feed pipe and a distribution plate to spin a fiber W, a cooling unit 4 that cools the fiber W spun from the spinning nozzle unit 3, a roller 5 that stretches and heat-treats the fiber W cooled by the cooling unit 4, and a winder 6 that winds the fiber W stretched and heat-treated by the roller 5.
The conjugate fiber fabricated by the above-described apparatus includes a sheath-core type, a side-by-side, a sea-island type, and so forth. These types of conjugate fibers can be fabricated by differently setting the configuration of the distribution plate and the flow path which are provided in the spinning nozzle unit 3.
FIG. 2 is a cross-sectional view of major parts to illustrate the spinning nozzle unit for fabricating the conjugate fiber of the sea-island type, for example. A spinning nozzle unit 3 for fabricating the conjugate fiber of the sea-island type includes multi-layered distribution plates 11 and 12, and a nozzle plate 13 positioned below the lowermost distribution plate 12. The respective distribution plates 11 and 12 is provided with a plurality of feed pipes 14 and 15 extending in a vertical direction, and the nozzle plate 13 is provided with a spinning nozzle 16 which is connected to the feed pipes 14 and 15. Spaces 17 and 18 are formed between the respective distribution plates 11 and 12 and the nozzle plate 13.
With the above configuration, after two kinds of resins each supplied into the spinning nozzle unit 3 from the molting extruder 2, for example, resin A (island component) and resin B (sea component), flow into the feed pipes 14 and 15 of the distribution plates 11 and 12 and the spaces 17 and 18, the resins are combined in the space 18 of the nozzle plate 13, and then are spun through the spinning nozzle 16 of the nozzle plate 13.
The fiber W spun by the spinning nozzle 16 has a cross sectional shape as follows, as illustrated in FIG. 3: a plurality of resins A (island component) are enclosed by one resin B (sea component). Since such a cross sectional shape is determined by the configuration of the distribution plates 11 and 12 and the feed pipes 14 and 15, the number and configuration of the distribution plates 11 and 12 and the feed pipes 14 and 15 to be installed may be varied to fabricate various types of conjugate fibers. Also, the conjugate fibers having specific cross sectional shapes are fabricated which are widely used in the fabrication of functional clothing, such as waterproof breathable clothing, quick-sweat-absorbing and quick-drying clothing, and microfiber, and which are used for a security yarn so as to prevent bills or certificates from being counterfeited.
According to the method and apparatus for fabricating the conjugate fiber according to the related art, since the specific cross sectional shape of the fiber is constantly maintained in the longitudinal direction of the fiber, composite components cannot be changed in the longitudinal direction of the fiber. Therefore, it is not possible to provide the fiber with various effects (dyeing difference, physical properties (strength, elongation, Young's modulus, boil-off shrinkage or the like), melting point, and so forth) of composite components in the longitudinal direction of the fiber. In particular, in the case of the security yarn using the conjugate fiber for use in the forgery protection of negotiable securities, since anti-forgery components which are different in the longitudinal direction of the fiber exist in parallel, there is a problem of interrupting the expression of security elements due to external stimulus (e.g., change in color or degradation in fluorescent performance). Therefore, it needs to improve such a problem.